There are a lot of issues with using lasers as weapons. First of all: the optics. For a laser to be useful as a weapon, you would have to focus the light as tightly as possible on the target. De-focus at all, and you might still blind them, but there won’t be much vaporization going on. The precision required for the optics to do this makes a hand-held laser really impractical. The slightest bump or wiggle and all of a sudden your gun is a high-powered flashlight.